ELIZABETH FARNSWORTH: Finally tonight, the latest on asthma, the most common chronic illness in children. Twelve to fourteen million people in the United States have asthma and more than four million of them are under the age of eighteen. The number of cases has more than doubled since 1980, as have deaths from the disease. Kids in America's inner cities are especially at risk. A study published today in the "New England Journal of Medicine" begins to explain why, and it involves cockroaches. With us to explain is Dr. Floyd Malveaux, dean of the Howard University College of Medicine. He co-wrote the study. Thanks for being with us, Doctor.
DR. FLOYD MALVEAUX, Howard University College of Medicine: It's a pleasure.
ELIZABETH FARNSWORTH: What were you seeing in the inner cities that made you start this study?
DR. FLOYD MALVEAUX: Well, I think my intro statement is quite accurate. We started to actually see an increase in the illness due to asthma in the 80's. The death rate also increased during the 80's. We saw a tremendous increase actually, of up to 50 percent increase in the death rates. And when we looked at the death rates or analyzed the death rates, the increase was primarily in minority populations, especially in African-Americans. At the beginning of the 80's, for example, for all age groups, African-Americans had a death rate twice as high as that of the rest of the population. But by the end of the 80's and the beginning of the 90's actually the death rate or the disparity between the two had risen to three to one, so most of that increase in death had occurred among minorities. In addition to that, not only did we see an increase in death rates, but we also saw an increase in the prevalence of this disease; that is, people, you know, actually having the disease, which saw an increase in the incidence. People developed the disease.
ELIZABETH FARNSWORTH: I read that 8.6 percent of the children in the Bronx have asthma.
DR. FLOYD MALVEAUX: Yes. That's also very interesting because it seems that among certain groups of individuals that the rate is disproportionately high. Among some Hispanic populations, for example, it is relatively high. Among African-Americans it is also slightly higher, but certainly not high enough to, I think, explain the disparity and the mortality and the morbidity that we're seeing.
ELIZABETH FARNSWORTH: So what did you find in the study?
DR. FLOYD MALVEAUX: In this particular study this study really is a take from I think other findings in the past, where people have looked at sensitivity to environmental allergens, or things that people are allergic to, with all those allergens. We've looked at allergens in inner-city populations because that's where a lot of the morbidity is. The illness--
ELIZABETH FARNSWORTH: Morbidity--
DR. FLOYD MALVEAUX: Being illness associated with asthma. So obviously we found that in this particular study there's a correlation between being allergic to cockroaches and also having a relatively high concentration of cockroaches within your own environment. That contributes to the illness.
ELIZABETH FARNSWORTH: In other words, if you have a lot of cockroaches, you tend to get allergic to them and then you develop asthma?
DR. FLOYD MALVEAUX: Yes.
ELIZABETH FARNSWORTH: How?
DR. FLOYD MALVEAUX: That is true, except that in order to develop the allergies you have to have the genetic predisposition to do that. So not everyone is going to develop allergies. Simply because you're exposed to high levels of cockroach antigen or allergen, so to speak, you won't necessarily develop the sensitivity to them.
ELIZABETH FARNSWORTH: What is asthma and how would a cockroach give it to you?
DR. FLOYD MALVEAUX: Yes. Well, asthma is a--is a problem of the lungs, where individuals have difficulty breathing. It's manifested by some wheezing sounds, tightness in the chest, sometimes coughing, especially coughing at night, and the reason for that is because there is partial obstruction of what we call the bronchial tubes or the air tubes, those tubes that carry the air directly into the lungs. Over time there may be inflammation actually within the walls of those two, again leading to that obstruction.
ELIZABETH FARNSWORTH: There have always been cockroaches in America. There have always been poor people in America. Why wouldn't there be more asthma now, and why would it be related to cockroaches?
DR. FLOYD MALVEAUX: Well, certainly we're not saying that because this study shows that there is this correlation that is necessarily the reason that we're seeing this tremendous increase, obviously not. I think that there are many factors associated with this. I think that really the reason we're seeing the increases related to poverty. People who live in poverty or live in crowded conditions. They have more cockroaches. They experience other problems as well. They have limited access to health care. I think that is contributing to the increase in the mortality and the morbidity of asthma.
ELIZABETH FARNSWORTH: And here you're talking about asthma overall, not just with children but asthma worldwide, which is going up dramatically.
DR. FLOYD MALVEAUX: That's correct.
ELIZABETH FARNSWORTH: And you think it has to do with poverty.
DR. FLOYD MALVEAUX: Absolutely. Because if you look in different populations, not only in this country, certainly in Australia and New Zealand, we see the same types of things. And among poor individuals there, the death rate is higher, the morbidity is higher. We've done the analyses in our cities here in this country. If you go into places like Chicago; Washington, D.C.; New York; and look at where the concentration of hospitalizations occur because of this disease, look at where most of the deaths occur in this disease, you will see them concentrated primarily in those areas where there is significant poverty.
ELIZABETH FARNSWORTH: If I have this cockroach problem and my kids had asthma or I had asthma, what should I do about it, what should one do?
DR. FLOYD MALVEAUX: Well, for anyone who has asthma, there are a couple of things, or a number of things that can be done. First of all, if you are allergic to something, first you should try to avoid it. Even if you're not allergic, if there are irritants, for example, like tobacco smoke, you have to avoid tobacco smoke, so clearly we recommend that individuals who have children with asthma should not be smoking in the home at all, not in the next bedroom or the next room, but not at all.
ELIZABETH FARNSWORTH: Trouble with cockroaches. They're really hard to get rid of it.
DR. FLOYD MALVEAUX: Cockroaches are difficult to get rid of, but we do have means, actually, of doing that. There are now from some compounds that--that are quite effective, but, you know, probably the best way to do this or to attack that problem is a good dose of education. And that is teaching people how to deprive cockroaches of food and water. That's what they desire. They will go where the food and the water is. So if there are no dirty dishes in the sink at night, for example, and we deprive them of that source of food and water, tie up the garbage, make sure they don't have access to that, they will go somewhere else and actually seek their food and water.
ELIZABETH FARNSWORTH: Some of the articles about your study have said that one of the reasons that the rate of asthma may be rising in inner cities among children and the tie-in to cockroaches is partly that kids are inside so much more, so they're spending more time perhaps in a bedroom eating in front of the TV, the cockroaches are in their bedroom, they sleep there, they're there all the time, because it's dangerous to be outside. Is that a misreading of your study?
DR. FLOYD MALVEAUX: I don't think we can interpret the study that way. I think that's an extension perhaps of what the data actually shows. Data in the study shows that there is a correlation between being allergic and having high levels of exposure in your environment. Then you are likely to have more symptoms, or you will have more symptoms. That's what the study shows. Why you are actually exposed to higher levels and so on is conjecture. Certainly if individuals spend more time in the homes now, then their exposure is going to be greater. So there may be some correlation here but the study really doesn't indicate that.
ELIZABETH FARNSWORTH: Well, thanks for being with us, Dr. Malveaux.
DR. FLOYD MALVEAUX: It's a pleasure.